Growing Sweet Potato, also Kumara

Ipomoea batatas : Convolvulaceae / the morning glory family

Jan F M A M J J A S O N Dec

Not recommended for growing in New Zealand - cool/mountain regions

  • Plant shoots or cuttings (Slips). Best planted at soil temperatures between 17°C and 35°C. (Show °F/in)
  • Space plants: 40 - 60 cm apart
  • Harvest in 15-17 weeks.
  • Compatible with (can grow beside): Best in Separate bed

Your comments and tips

09 Mar 19, Andrea (New Zealand - temperate climate)
Hi there,I live in chilly chch but want to attempt to grow kumera. I had one sprouting so I cut it in half and put it in water and now it's sprouting . But it's the wrong time of yr,March to plant them . How can I keep my sprout until October ? Thanks
10 Mar 19, Mike Logan (New Zealand - temperate climate)
It may survive if you plant it now - might not grow much or produce a crop. Might be better to try again say Oct and plant out Nov Dec. You are temperate climate.
30 Oct 18, Mike (New Zealand - temperate climate)
Here is how they grow them commercially in sub tropical southern Queensland Australia. They hill the soil up with a 2' base and about 1' high - paddock looks like corrugated iron - wave pattern. They then take cuttings (called slips about 50-60cm long) of vine from a pre-existing growing plant. These are planted (in the top part of the mound) horizontally into the soil with just the tip sticking out of the soil. Keep well watered the first week or two until the plant starts growing. Good rich soil to start with and then do not fert again especially with N. You want root development not vine production. If looking for cuttings/slips/tubers ask friends/neighbours/produce companies/internet sites etc or start a tuber as stated here.
26 Oct 18, Julie McLean (New Zealand - temperate climate)
I'm a very beginner gardener and want to try my hand at kumara . Your advice and comments are helpful and interesting. Thanks Julie.
10 Mar 19, Andrea (New Zealand - temperate climate)
Hi Julie,I'm also a beginner so all the best with growing your kumera. I'm in chch so it will be a challenge I think !
18 Oct 18, john ward (New Zealand - sub-tropical climate)
where can i get some orange kumara cuttings .Not easy to find im having problems trying to get them sprouting
23 Oct 18, Mike (New Zealand - temperate climate)
Ask around nurseries or produce/farming depots /supply companies or phone some of them.
02 Oct 18, Warren Leedes (New Zealand - cool/mountain climate)
Firstly thanks for the web site I would like to grow the different coloured Kumara, how do I go about getting seeds please? Any advice would be gratefully received Kind regards Warren Leedes
04 Oct 18, Paul (New Zealand - sub-tropical climate)
Plant the tubers that you want to grow but in a separate bed. They will sprout lots of shoots which will also have roots near the base. When the shoots are 40 to 50 cm long put a fork under the tuber and gently lift it out. Separate the shoots and plant them in the bed you have prepared for them as indicated in the article above. Last year, before I knew this, I planted several tubers where I wanted them to grow but after learning the right method I dug up three and planted out about 50 slips. The slips can be left in water while you are waiting to plant them out and in a few days mine put out prolific roots where the base was under water. You can also start the sprouting inside, cutting the tops off tubers and putting the cut down in shallow water, then planting them out when they start to sprout. Roots will also start growing but later than the shoots. Look for the eyes in the tubers as they are where the shoots come from.
08 Oct 18, Mike (New Zealand - sub-tropical climate)
Also you can use 50-60cm sections of the growing plants 6-8 week old and plant them along the ground with the tip out of the soil. Roots will grow from where each leaf joins the vine.
Showing 21 - 30 of 58 comments

Annie...We simply bought a small kumara from a local supermarket, suspended it with toothpicks in a cut off coke bottle of water. When the shoots, or "slips" began to sprout (2-3wks) we then placed them in a small jam jar of water until roots began to develop, then planted out in fish bins of potting mix. We were late- late Dec & Jan, have just harvested. A lot were long & skinny, but perfect for the hot air cooker & crockpot. Some were like the shop sizes! We ended up with about 3-4 kg from a single 300g kumara (it's still growing sprouts on the laundry windowsill)! Hope this helps someone out there. Best wishes...

- Richard Clough

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